[PATCH AUTOSEL 4.14 18/19] ocfs2: quota_local: fix possible uninitialized-variable access in ocfs2_local_read_info()

From: Sasha Levin
Date: Thu Sep 09 2021 - 21:05:35 EST


From: Tuo Li <islituo@xxxxxxxxx>

[ Upstream commit 6c85c2c728193d19d6a908ae9fb312d0325e65ca ]

A memory block is allocated through kmalloc(), and its return value is
assigned to the pointer oinfo. However, oinfo->dqi_gqinode is not
initialized but it is accessed in:
iput(oinfo->dqi_gqinode);

To fix this possible uninitialized-variable access, assign NULL to
oinfo->dqi_gqinode, and add ocfs2_qinfo_lock_res_init() behind the
assignment in ocfs2_local_read_info(). Remove ocfs2_qinfo_lock_res_init()
in ocfs2_global_read_info().

Link: https://lkml.kernel.org/r/20210804031832.57154-1-islituo@xxxxxxxxx
Signed-off-by: Tuo Li <islituo@xxxxxxxxx>
Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx>
Reviewed-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
Cc: Mark Fasheh <mark@xxxxxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Cc: Changwei Ge <gechangwei@xxxxxxx>
Cc: Gang He <ghe@xxxxxxxx>
Cc: Jun Piao <piaojun@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ocfs2/quota_global.c | 1 -
fs/ocfs2/quota_local.c | 2 ++
2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index d212d09c00b1..f78e5294f5d2 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -356,7 +356,6 @@ int ocfs2_global_read_info(struct super_block *sb, int type)
}
oinfo->dqi_gi.dqi_sb = sb;
oinfo->dqi_gi.dqi_type = type;
- ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo);
oinfo->dqi_gi.dqi_entry_size = sizeof(struct ocfs2_global_disk_dqblk);
oinfo->dqi_gi.dqi_ops = &ocfs2_global_ops;
oinfo->dqi_gqi_bh = NULL;
diff --git a/fs/ocfs2/quota_local.c b/fs/ocfs2/quota_local.c
index 16c42ed0dca8..b5216ed38e8d 100644
--- a/fs/ocfs2/quota_local.c
+++ b/fs/ocfs2/quota_local.c
@@ -703,6 +703,8 @@ static int ocfs2_local_read_info(struct super_block *sb, int type)
info->dqi_priv = oinfo;
oinfo->dqi_type = type;
INIT_LIST_HEAD(&oinfo->dqi_chunk);
+ oinfo->dqi_gqinode = NULL;
+ ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo);
oinfo->dqi_rec = NULL;
oinfo->dqi_lqi_bh = NULL;
oinfo->dqi_libh = NULL;
--
2.30.2